Titre du document / Document title

Regressionsanalyse des idiopatischen Endothelzellverlustes nach perforierender Normalrisiko-Keratoplastik: Grundlage für die Langzeitanalyse von Endothelschädigungsfaktoren in einer retrospektiven klinischen Studie = Regression analysis of chronic endothelial cell loss after penetrating normal-risk keratoplasty: a retrospective clinical study

Auteur(s) / Author(s)

BÖHRINGER Daniel ⁽¹⁾ ; REINHARD Thomas ⁽¹⁾ ; GODEHARDT Erhard ⁽²⁾ ; SUNDMACHER Rainer ⁽¹⁾ ;

Affiliation(s) du ou des auteurs / Author(s) Affiliation(s)

⁽¹⁾ Augenklinik, Heinrich-Heine Universität, Moorenstr. 5, 40225 Düsseldorf, ALLEMAGNE
⁽²⁾ Arbeitsgruppe Biometrie, Klinik für Herz-und Thoraxchirurgie, Heinrich-Heine Universität, Moorenstr. 5, 40225 Düsseldorf, ALLEMAGNE

Résumé / Abstract

Background: For the characterisation of influencing factors on chronic endothelial cell loss after penetrating keratoplasty by means of multivariate statistics, a mathematical description of the course of the individual postoperative endothelial cell density is a prerequisite. This mathematical description should result in a standardized index value describing course and amount of the postoperative endothelial cell loss over time in a canonical way. The slopes of the linear regression lines for each individual scatter plot of a) the endothelial cell density values plotted against the respective postoperative time directly (linear regression), and b) after logarithmic transformation (exponential regression) are evaluated, respectively. Patients and methods: 58 patients after normal-risk keratoplasty (26 × keratokonus, 22 × Fuchs-dystrophy and 10 cases of corneal decompensation after cateract surgery) with 5 or more postoperatively acquired endothelial density values and without any episodes of graft rejection were included in this study. Mean follow up was 2.9 ± 1.1 years. The postoperative endothelial cell density values were plotted against the respective time for each patient individually. The coefficients of variation (R²) derived from the linear and the exponential regression models were calculated for each of these scatter plots. The pairs of R² values (linear vs. exponential) were compared statistically. A dependence of the difference of linear and exponential Revalues on the ophthalmologic diagnosis was tested as well. Results: The linear model is able to declare 83% the total variance of the course of the endothelial cell densitiy. The exponential model even declares 86%. This small difference was statistically significant. Since both methods of regression describe the course of the cell density well, intra/ and extrapolation of missing endothelial values is possible with both models. No dependence of the difference of linear and exponential R^2- values on the ophthalmologic diagnosis could be demonstrated. Conclusions: Both, the intuitively understandable slope of the linear regression line and the constant of decay of the exponential regression curve, are suitable for describing the amount of the postoperative loss of endothelial cells after normal-risk keratoplasty independant of the ophthalmologic diagnosis. Both can thus be used as target variable in forthcoming statistical analyses for chronic endothelial cell loss.

Revue / Journal Title

Klinische Monatsblätter für Augenheilkunde   ISSN 0023-2165   CODEN KMAUAI 

Source / Source

2001, vol. 218, n^o6, pp. 412-417 (14 ref.)

Langue / Language

Allemand

Editeur / Publisher

Thieme, Stuttgart, ALLEMAGNE  (1963) (Revue)

Mots-clés anglais / English Keywords

Keratoplasty ; Penetrant ; Postoperative ; Loss ; Chronic ; Endothelial cell ; Regression analysis ; Statistical analysis ; Statistical model ; Evaluation ; Cornea ; Human ; Surgery ;

Mots-clés français / French Keywords

Kératoplastie ; Pénétrant ; Postopératoire ; Perte ; Chronique ; Cellule endothéliale ; Analyse régression ; Analyse statistique ; Modèle statistique ; Evaluation ; Cornée ; Homme ; Chirurgie ;

Mots-clés espagnols / Spanish Keywords

Queratoplastia ; Penetrante ; Postoperatorio ; Pérdida ; Crónico ; Célula endotelial ; Análisis regresión ; Análisis estadístico ; Modelo estadístico ; Evaluación ; Córnea ; Hombre ; Cirugía ;

Localisation / Location

INIST-CNRS, Cote INIST : 3850 A, 35400009853582.0030